Insulated electric conductor.



No. 666,003. Patented Ian. l5, I90l. W. L. R. EMMET.

INSULATED ELECTRIC CONDUCTOR.

(Application filed Aug. 19, 1899.]

(No Modal.)

Mtnesses Inventor.

\MHiam L R Emmet WM; $2M

THE uukms PETERS co. wonxumo.wuummon. a. c.

' NITED STATES PATENT FFICE.

WILLIAM L. R. EMMET, OF SCHENECTADY, NEYV YORK, ASSIGNOR TO THE GENERALELECTRIC COMPANY, OE NEW YORK.

INSULATED ELECTRiC CONDUCTOR.

SPECIFICATION forming part of Letters Patent No. 666,003, dated January15, 1901.

Application filed August 19, 1899. Serial No. 727,742. (No model.)

To aZZ whom, it may concern.-

Be it known that I,WILLIAM LE ROY EMMET, a citizen of the United States,residing at Schenectady, in the county of Schenectady, State of NewYork, haveinvented certain new and useful Improvements in InsulatedElectric Conductors, (Case No. 1,058,) of which the following is aspecification.

The object of my present invention is to provide a cheap and effectiveinsulating covering for an electric conductor or cable having highinsulating properties and proof against deterioration under the effectsof heat and moisture.

In carrying out my invention I apply to the conductor a paper coveringcoated with gum or varnish containing an excess of oxidizable Vegetableoil which may be applied in a state of sol ution or fusion and thendried or hardened. A plurality of such coverings are Wound upon theconductor, so as to lap joints, the successive layers being treated withadditional coatings of moisture-proof insulating material. Each layer ofpaper is preferably coated a number of times With the insulatingcompound, each coat being permitted to dry or harden before the next isapplied.

The features of novelty of my invention will be particularly describedhereinafter and will be definitely indicated in the claims.

In the accompanyingdrawings, which illustrate as a type of conductor anelectric cable provided with my improvements, Figure 1 is a sideelevation with parts broken away, showing the manner of insulating thecable. Fig. 2 is a sectional view of a completed cable.

1 represents a group of electric conductors which may be separatelyinsulated or not, according to the ultimate object of the conductor.Upon this I Wind a paper ribbon 2, coated with an insulating gum orvarnish. The compound I prefer to employis one containing boiledlinseed-oil or other vegetable oxidizing-oil which in hardening Willyield a dense tough insulator. I find excellent results from a moistureof about eighty parts of boiled linseed oil and twenty of rosin, whichmay be thinned for application by a solvent, such as benzin, or may beapplied hot. The ribbon may be carried through a preliminary bath of theinsulating material and then carried through a drying-box before beingwound upon the conductor or may be wound and then coated a number oftimes, each coat beingpermitted to harden and oXidize before the next isapplied. The paper may he wound in a close spiral, so as to practicallycover the conductor throughout its length, and then coated as often asdesired with the insulating material, so as to render the jointsmoisture-proof. A second serving of the coated paper 3 is then Wound onthe first layer, so as to lap over the joints between contiguous turnsof the first serving, and this is subsequentlysimilarly coated with alayer or layers of insulating material to render its jointsmoisture-proof. Any desired number of servings may thus be placed aroundthe conductor or cable, and when a sufficient depth of insulation issecured it may be iuclosed Within an armor or tube at to protect itagainst wear and water. The varnished or coated paper effectively guardsthe conductor against the entrance of moisture from the air and in theprocess of drying fills the pores of the paperand displaces the air andany moisture it may carry, thus prod ucing a fabric of greaterresistance than the paper alone would possess and preserving it againstdeterioration by subsequent exposure in service.

Insulation of the kind described not only effectively protects theconductor against entrance of moisture at points where the armor isdamaged, but also withstands heat well and does not deterioratematerially under prolonged exposure to moderately high temperatures. Infact, a conductor insulated as described will withstand temperatureswhich will not injure paper or other fabric used for the application ofthe compound, as the latter will not fuse down as do the compoundscommonly applied to conductors.

My invention is not restricted to any particular type of insulatingcompound; but for 5 the purpose of convenience in manufacture it shouldbe such as will not melt down on increase of temperature and may be laidon in a liquid state, which not only permits uni form and thin coating,but facilitates infil- 10o tration into the poresof the paper and abetter resulting product and permits a smooth even coat to be appliedover the previouslyapplied and oxidized coat.

W'hat I claim as new, and desire to secure by Letters Patent of theUnited States, is

1. An electric conductor or cable provided with two or more layers ofnon-conducting fabric, the several layers arranged to lap joints, andprovided each with a plurality of thin coatinv's of an insulatingcompound containing oxidized oil in excess.

2. An electric conductor or cable provided With a helical Winding ofpaper coated with a plurality of adherent layers of a vegetable oil,each layer being separately oxidized and hardened.

3. An electric conductor or cable, provided with a plurality of fibrouswindings each having a number of heat-refractory coats of insulatingcompound containing; oxidized oil in excess.

l. An electric conductor or cable provided with a plu 'ality of layersof paper wound thereon so as to lap joints, the several layers beingcoated with a number of layers of insulating material coniaiuinuoxidized oil in excess, and a protective armor around the insulatedconductor.

5. An electric conductor or cable covered with fiber coated with anumber of mutually adherent heat-relt'ractory thin laminae of insulatingcompound containing oxidized oil in excess.

In witness whereof I have hereunto set my hand this 17th day of August,1899.

Witnesses:

BENJAMIN B. HULL, EDWARD WLLLnuns, Jr.

